Evacuable container having one-way valve with filter element

ABSTRACT

A one-way valve allows air to be drawn from a collapsible, flexible, air-tight bag using a vacuum source. When the vacuum source is removed, the one-way valve prevents air from re-entering the bag. A filter is placed on the valve body to prevent small particles from the bag from clogging the valve or the vacuum source.

RELATED APPLICATIONS

This application is a divisional of application Ser. No. 09/310,468,filed May 12, 1999 now U.S. Pat. No. 6,408,872, and incorporatedhereinby reference, which is a continuation-in-part of application Ser.No. 08/851,361, filed May 5, 1997, now issued as U.S. Pat. No.5,931,189, which is a continuation of application Ser. No. 08/423,761,filed Apr. 17, 1995, now abandoned which is a divisional of applicationSer. No. 08/168,963 filed Dec. 15, 1993, now issued as U.S. Pat. No.5,480,030.

FIELD OF THE INVENTION

The present invention relates to evacuable storage containers, and inparticular to filters for one-way valves used in such storagecontainers.

BACKGROUND

Collapsible, evacuable storage containers typically include a flexible,air-tight bag, an opening through which to place an article in the bag,and a fixture through which to evacuate excess air. A user places anarticle into the bag through the opening, seals the opening, and thenevacuates the air in the bag through the fixture. With the bag thusevacuated, the article contained therein may be significantly compressedso that it is easier to transport and requires substantially lessstorage space.

Collapsible, evacuable storage containers are beneficial for reasons inaddition to those associated with compression of the stored article. Forexample, removal of the air from the storage container inhibits thegrowth of destructive organisms, such as moths, silverfish, andbacteria, which require oxygen to survive and propagate. Moreover, suchcontainers, being impervious to moisture, inhibit the growth of mildew.

Not only large, compressible items such as clothing may be stored in acollapsible, evacuable storage container. For example, it may bedesirable to store bulk items made of small particles, such as powdersor granulated resins, in an evacuated container. One situation thatcommonly occurs is that a particular bulk item is shipped in a large,rigid container such as a drum. Bulk items may be moisture sensitive andare sealed against moisture during shipment. But many times a user doesnot need to use the entire contents of the large container, and so onceexposed to air the remaining bulk contents quickly become unusable andare thus wasted.

One collapsible, reusable, evacuable storage container is shown in theabove-referenced U.S. Pat. No. 5,480,030 issued to Sweeney et al., undercommon ownership with the present invention, and incorporated herein byreference in its entirety. The '030 patent discloses a one-way air valveassembly having a flexible diaphragm that seals against a valve seat.The valve assembly also has vanes positioned to prevent the bag materialor bag contents from obstructing air holes or the diaphragm while air isbeing evacuated through the valve assembly. These vanes may protectagainst the bag material, or against large objects stored in the bag,but the vanes do not prevent small particles from entering the air holesand either blocking air holes or preventing the diaphragm from properlyclosing once evacuation is complete. Furthermore, small particles may becarried through the valve and become lodged in the vacuum producingdevice used to evacuate the storage container, thus affecting operationof the vacuum producing device.

Therefore the need exists for a reusable, collapsible, evacuable storagecontainer that may store bulk items that include particles or granules.

SUMMARY

Embodiments of the invention are directed to collapsible, evacuablestorage containers. These storage containers have a one-way valveassembly allowing air to pass out of a flexible, air-tight bag, but notto return to the bag through the valve assembly. A filter is configuredto be fitted against the one-way valve assembly so that material in thebag does not pass into or through the valve assembly when air isevacuated from the bag.

In one embodiment of the invention, the filter is made to be compatiblewith an existing one-way valve assembly. A filter assembly is formed ofa cylinder capped by a top portion. The top portion has air slotsthrough which air passes before entering the one-way valve assembly. Afilter element is placed in the filter assembly so that air passingthrough the air slots is filtered. Embodiments of the invention mayinclude filter elements providing filtration for various particulatesizes.

In an embodiment of the invention, the cylinder of the filter assemblycontains a plurality of slots so that the filter assembly may be placedover radial vanes on the valve body. These slots are formed so that whenthe filter assembly is pressed onto the valve assembly, a seal is formedbetween the filter assembly and the vanes. In one embodiment of theinvention, an annular lip is positioned at the base of the cylinder.This lip is configured to seal the filter assembly against acorresponding inner wall of the valve assembly.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an embodiment of the invention.

FIG. 2 is a perspective view of a flexible bag.

FIG. 3 is an exploded perspective view showing an embodiment of a valveassembly and of a filter assembly.

FIG. 4 is a plan view showing an embodiment of a filter assembly inposition on a valve assembly.

FIG. 5 is a cross-sectional view showing an embodiment of a filterassembly mated with a valve assembly.

FIG. 6 is a perspective view showing another embodiment of theinvention.

DETAILED DESCRIPTION

In the drawings that accompany this description, the same numberedelements shown in separate figures are intended to represent similarelements. The embodiment of the filter assembly shown in theaccompanying drawings is intended to be fitted against an existingone-way valve in an existing collapsible, evacuable container. Thiscontainer is known as a SPACE BAG, and is manufactured by NEW WESTPRODUCTS, INC. of Redwood City, Calif. Those skilled in the art willappreciate that embodiments of the filter assembly may be adapted foruse with a wide variety of one-way valves and containers.

FIG. 1 is a perspective view of an embodiment of the invention. Anevacuable container 2 includes a bag 4, a valve assembly 6, and a seal8. During use, one or more discrete articles or a bulk material may beplaced in bag 4, after which bag 4 is sealed using seal 8. Air is drawnout of bag 4 through valve assembly 6 using a conventional vacuumsource, such as a household or industrial vacuum cleaner. Valve assembly6 and seal 8 maintain the vacuum inside bag 4 when the vacuum source isremoved. Details regarding embodiments of valve assembly 6 are discussedin U.S. Pat. No. 5,480,030, mentioned above, and also in applicationSer. No. 08/851,361 incorporated herein by reference in its entirety.Additional embodiments of valve assembly 6 are discussed below and shownin the accompanying drawings. In one embodiment, seal 8 is aninterlocking air tight Zipper-type fastener manufactured byMinigrip/Zip-Pak (An ITW Company) of Mission Viejo, Calif.

FIG. 2 illustrates an embodiment of bag 4. Bag 4 has a hole 10 in whichto install valve assembly 6, and an opening 12 through which articles orbulk material may be placed for storage. Details regarding embodimentsof bag 4 are discussed in U.S. Pat. No. 5,480,030, mentioned above. Inone embodiment the bag is constructed of a blended extrusion layer ofpolyethylene sandwiched between a nylon layer and a layer ofpolyethylene sheeting. In some embodiments materials comprising the bagmay be altered so as to prevent interaction with the bag contents. Sucha custom bag composition is based on user need and may be determinedusing material qualities known in the art or by experimentation.

FIG. 3 is an exploded perspective view showing valve assembly 6 andfilter assembly 14. As shown, valve assembly 6 is comprised of a base16, a retaining ring 18, and a valve element 20. Valve assembly 6 ismounted to bag 4 (FIGS. 1 and 2) such that flange 17 of base 16 is onthe inside of bag 4. Base 16 extends through hole 10 and is held inplace by retaining ring 18 placed over base 16 on the outside of bag 4.

Valve element 20 provides the one-way feature in valve assembly 6. Inthe embodiment shown, valve element 20 is made of conventional clearpolyvinylchloride (PVC). Valve element 20 has an outer annular portion22 and an inner diaphragm 24. Annular portion 22 functions as a faceagainst which a vacuum source, such as a conventional household orindustrial vacuum cleaner nozzle (FIG. 6), may be sealed as the nozzleis pressed against base 16. When the nozzle is in place and a vacuumpressure draws air through the nozzle, diaphragm 24 flexes open and airpasses through a plurality of holes 26 in base 16. When the nozzle isremoved, diaphragm 24 returns to its original shape and seals againstbase 16, thus preventing air from passing back through holes 26.

As shown, a plurality of radial vanes 28 separate holes 26. Vanes 28hold a central valve element support 29. Thus each of holes 26 is formedas the open space bounded by recessed portion 16B of base 16, two eachof vanes 28, and valve element support 29. FIG. 5 provides another viewof holes 26. As shown, vanes 28, spaced around support 29, are separatedby holes 26.

Referring again to FIG. 3, filter assembly 14 fits against valveassembly 6. Filter assembly 14 is comprised of a top portion 30 and acylindrical sidewall 32. Other embodiments may have different sidewallshapes, the sidewall being adapted for use with a particular valve base.As shown, filter assembly 14 fits against base 16 to form a seal tightenough to keep any material stored in bag 4 from passing into valveassembly 6. In some embodiments this seal may be air-tight. A pluralityof slots 34 in filter sidewall 32 are configured to fit over respectivevanes 28 in base 16. A raised annular lip 36 fits against base 16'sinner wall 38. Details of the fit between filter assembly 14 and base 16are discussed in detail below.

Filter assembly 14 has a plurality of openings 40 through which airpasses while being drawn through valve assembly 6. As shown, openings 40are arranged in a series of fan-shaped patterns having curved slots.Other embodiments of filter assembly 14 may use different shapes andpatterns for openings 40. A filter element 42, visible for examplethrough one of the openings 40, is placed underneath top portion 30 andunderlies openings 40 to prevent stored material from entering valveassembly 6.

In one embodiment, filter assembly 14 is made of conventionalpolyethylene. In another embodiment, filter assembly 14 may be made ofacrylonitrile-butadiene-styrene (ABS), known by trade names such asCYCOLAC or LUSTRAN. Some embodiments of the filter are injection molded.Other embodiments may be made using conventional fabrication methodssuch as milling. The material forming filter assembly 14 is soft, sothat a slight deformation occurs as filter assembly 14 is pressedagainst base 16, as described below. The deformation provides both aseal and friction by which filter assembly 14 stays in place.

In one embodiment of the invention, filter element 42 is a 47 millimeterdiameter, 0.02 micrometer PTFE membrane filter, supplied by Paul GilmanLaboratories of Fremont, Calif., as part S-66143, TF-200. The 47 mmfilter element is then cut to slightly less than 1.34 inches so as tofit within filter assembly 14. Embodiments of this invention are notrestricted to using this filter element type only, however, and otherembodiments may use other filter element types. For example, filterelement 42 may be optimized for a certain type of material to be storedwithin an evacuable container. User requirements may dictate filterelement 42 composition. Filter element 42 may be attached to filterassembly 14 using various methods. For example, in one embodiment,filter element 42 is attached to filter assembly 14 using direct heattransfer. In other embodiments, sonic welding or other adhesive orconnecting methods may be used. Filter assembly 14 may be permanentlyattached to base 16, or filter assembly 14 may detachable from base 16in order to, for example, permit filter element 42 to be replaced.

As mentioned above, slots 34 are configured to fit over vanes 28. Insome embodiments in which vanes are not used, however, slots 34 may beomitted. In one embodiment, each slot 34 is 0.060±0.002 inch wide and0.47 inch long to ensure an adequate seal when filter assembly 14 ispressed onto base 16.

In the embodiment shown, a raised annular lip 36 is positioned aroundthe base of sidewall 32. This lip 36 adds extra tension to the junctionof, and improves the seal between, sidewall 32 and base 16. Annular lip34 provides an improved seal between filter assembly 14 and base 16 overa seal between a straight edge junction of sidewall 32 and base 16.

FIG. 4 is a plan view showing an embodiment of filter assembly 14mounted on an embodiment of base 16. As depicted, filter assembly 14fits over a plurality of radial vanes 28 (partially hidden by filterassembly 14) positioned on base 16.

FIG. 5 is a cross-sectional view showing an embodiment of valve assembly6 mated with filter assembly 14, taken at cut line A—A in FIG. 4. Valvebase 16 is shown inserted through a flexible, air-tight bag 4 and heldin place by an annular retaining ring 18. An opening 50 is provided inbase 16 in which a nozzle (FIG. 6) from a vacuum source is placed todraw air through the valve. In some embodiments, a removable cap (notshown) may be placed over opening 50 to protect inner portions of valveassembly 6. A plurality of vanes 28 are positioned on the underside ofbase 16.

Flexible diaphragm 24 is shown in position against a seat 52. Asdescribed above, when a vacuum source nozzle is placed into opening 50,vacuum pressure causes diaphragm 24 to flex and allow air, representedby arrow 54, to be drawn through valve assembly 6. When the vacuumsource nozzle is removed, diaphragm 24 returns to its position sealedagainst seat 52 so as to prevent air from flowing in a reverse directionthrough the valve. In the embodiment shown, diaphragm 24 and annularportion 22 are an integral piece, joined by two small bridge pieces(FIG. 3).

As mentioned above, further details regarding evacuable containers andone-way valves are given in U.S. Pat. No. 5,480,030, and in applicationSer. No. 08/851,361.

Still referring to FIG. 5, filter assembly 14 is shown mated with valvebase 16. Lip 36 is shown sealing sidewall 32 against valve base innersurface 38. As shown, filter assembly 14's sidewall bottom surface 37 isshown sealed against base 16's surface 56, although in other embodimentsa slight gap is allowable due to the seal between lip 36 and surface 38.

Also shown is a vane 28A extending through a slot 34 in filter assembly14. It may be seen that the length of slot 34 should not exceed theheight of a vane 28, or else leakage may occur near the top junction 58.

Filter element 42 is shown attached to the underside of filter assembly14's top portion 30. Filter element 42 is positioned so that air,represented by arrow 54, is filtered as it passes through each of theseveral air holes 40.

FIG. 6 is a perspective view showing an embodiment of the inventionduring use. A container 70 is shown having a bag 4 placed in a rigidvessel 71 to allow easier handling of a stored bulk material such as apowder or granules. The rigid vessel should be strong enough to hold thedesired bulk contents during routine handling. In some embodiments therigid container may be a conventional container made of plastic,corrugated fiber, bonded fiber, wood, or metal. In other embodiments thecontainer may be custom-fabricated to meet user needs. In someembodiments, the rigid vessel 71 may be omitted.

Stored material may be placed in bag 4 so as to fill vessel 71. Asshown, however, a portion of stored bulk material has been removed frombag 4, illustrating the reusable nature of the evacuable container 70.Bag 4 has been sealed with seal 8. A nozzle 72 from a vacuum source 74is placed, by hand for example, against valve assembly 6. As describedabove, vacuum source 74 draws air out from bag 4 through valve assembly6. When sufficient air has been withdrawn from bag 4, nozzle 72 isremoved and both valve assembly 6 and seal 8 prevent air from reenteringbag 4. If at a later time an additional portion of material stored inbag 4 is to be taken, seal 8 is opened, the material is removed from bag4, and then bag 4 is resealed and reevacuated as described.

An advantage of embodiments of this invention is that it provides areusable, evacuable container for granular or powdered bulk material.Such bulk materials may include items such as nylon resins, tea, cork,and foam products. Embodiments of the filter assembly prevent the bulkmaterial from entering and clogging both valve assembly 6 and the vacuumsource used to evacuate bag 4.

Another advantage of the embodiment shown and described is that filterassembly 14 may be removed and replaced with a fresh assembly if thefilter element 42 becomes clogged. As shown in FIG. 6, a user opens seal8 and reaches into bag 4 to remove and replace filter assembly 14. Inother embodiments, however, filter assembly 14 may be permanentlyattached to, or formed as an integral part with, valve assembly 6.

We claim:
 1. A method of manufacturing a storage container, comprisingthe acts of: providing a flexible, air-tight bag having an opening forinserting material to be stored; providing an air-tight seal across theopening; providing a one-way valve assembly installed in the bag,wherein the valve assembly comprises a plurality of vanes and allows airto pass out of the bag but prevents air from entering the bag; andproviding a filter assembly shaped to mate with the valve assembly, tofit over the vanes, and to form a seal with the vanes, wherein thefilter assembly comprises at least one hole formed therein, and whereinthe filter assembly supports a filter element across the or each holesuch that air passing out of the bag through the valve assembly isfiltered.
 2. The method of claim 1, wherein the air-tight seal isresealable.
 3. The method of claim 1, wherein the filter assembly isheld against the valve assembly by friction.
 4. The method of claim 1,wherein the filter assembly is made to be removable from the valveassembly so that a second filter assembly may be mated with the valveassembly.
 5. The method of claim 1, wherein the filter assemblycomprises: a cylindrical side wall having an outside surface and a firstend; a top portion positioned as a cap over the side wall at the firstend; and a raised annular lip positioned on the outside surface at anend opposite the first end, wherein the annular lip is configured toseal against a surface of the valve assembly.
 6. The method of claim 1comprising the act of providing the valve assembly and the filterassembly as an integral piece.
 7. The method of claim 1 comprising theact of providing the filter element to prevent particles of a materialstored in the bag from entering the valve assembly.
 8. The method ofclaim 1, wherein the filter element comprises an about 0.02 micrometerfilter.
 9. The method of claim 1 comprising the act of providing a rigidvessel into which vessel the bag is placed.
 10. The method of claim 1,wherein the one-way valve assembly is configured to receive a nozzlecoupled to a vacuum source.
 11. A method of manufacturing a storagecontainer, comprising the acts of: providing a flexible, air-tight baghaving an opening for inserting material to be stored; providing anair-tight seal across the opening; providing means for allowing air topass out of the bag but not to pass into the bag, wherein the means forallowing air to pass out of the bag but not to pass into the bagcomprises a plurality of vanes; and providing means for filtering airpassing out of the bag, wherein the means for filtering air passing outof the bag comprises at least one hole formed therein, wherein the meansfor filtering air passing out of the bag supports means for filteringair passing through the or each hole, and wherein the means forfiltering air passing out of the bag comprises a plurality of slotsshaped to receive the vanes.
 12. The method of claim 11, wherein theseal is resealable.
 13. The method of claim 11, wherein the means forfiltering air passing through the or each hole is held by frictionagainst the means for allowing air to pass out of the bag but not topass into the bag.
 14. The method of claim 11, wherein the means forfiltering air passing out of the bag is made to be removable from themeans for allowing air to pass out of the bag but not into the bag. 15.The method of claim 11, wherein the means for filtering air passing outof the bag prevents particles of a material stored in the bag fromentering the means for allowing air to pass out of the bag but not topass into the bag.
 16. The method of claim 11 furtherer comprising theact of providing means for rigidly supporting the bag.
 17. The method ofclaim 11, wherein the means for allowing air to pass out of the bag butnot to pass into the bag is configured to receive means for coupling toa vacuum source.